Eccentric type steel plate lifting clamp



July 3, 1945. J. c. RENFROE 2,379,552

' ECCENTRIC TYPE STEEL PLATE LIFTING CLAMP Filed July 10, 1944 2 Sheets-Sheet 1 M ML. M km',

July 3, 1945. J. c. RENFROE ECCEN'I'RIQ TYPE STEEL PLATE LIFTING CLAMP Filed July 10, 1944 2 Sheets-Sheet 2 Patented July 3, 1945 i mm STATES P IQ C i 1, ft CEN C- BE STEEL P J I I G a F ii Joseph o. Renfroe, Jacksonville, Fla,

" Applicants unie, 1944', ser alivcls aaii Claims. (Gazer-ion My invention relates to improvements in steel plate lifting clamps, and more ijparticularly to a platevliiting clamp of the eccentric type in which a pivoted plate clamping jaw is moved into clamping; engagement with a steel plate on which the, clamp is placed when apull is put ontheliftclampbody. if i Anpbject of, invention is to provide an ;im-, proved steel platelifting clamp which will be pro-, videdwith a plate receiving slot and a swivel jaw ing cable attached to, aneye in theouter end of the eccentric head; or,shackle1attached tothe and pivoted jaw mounted at the oppositesides of the slot, said; pivoted clamping jaw being brought into automatic operation by means f an eccentric head member and interconnected cam links, when a pull is exerted on the lifting cable attached to an eye in the free end or outer end of the said shackle Or eccentric head member.

Another object of my invention is to provide an,

improved eccentric type steel plate lifting clamp,

which will include a slotted body adapted to support a swivel jaw and a pivoted jaw at the opposite sides of said slot, said body being further provided with a centrally disposed upwardly extending guide head formed withan elongated bearing slot in alinement with the hereinbefore mentioned .slot in the clamp body, and a split eccentric shackle mounted on said guide head upon a pin movabl in the slot in the guide head, together with a pair of interconnecting cam links operatively connected between the ends of said otedq jaw :member in retracted or unclamped position. l a a l T Like characters of reference areused throughoutth following specificationand theaccompanying udrawings to designate corresponding parts. :1 l M l i,

rIn carrying out my invention I provide animproved automatically operated eccentric type steel plate lifting clamp havinga bodyl formed with a plate receiving slot 2 in its lower edge, and

a it centrally disposed upwardly extending guide head 3 formedwith'an elongated bearing slot 4 arranged, in alinement with the said-plate receiving-slot ,2 in the body]. A fixed or swivel jaw 5 will be received in one face of the plate receivin s1ot2in the body I, the same being held in place by means ofthe pins, and the opposite side of.

the slot 2 willbe formed by the spaced depending legs 1, between which the bearing pin 8 is mounted to support the pivoted steel plate clamping jaw 9, the plate engagingportion of the clamping jaw being provided with the toothed surface l0.

From the drawings, it will be apparent that spaced bearing surfaces H will be formed on the body I at the base of and at the opposite sides pin and the free or outer end of the pivoted clamping jaw, whereby any lift on the shackle will cause an immediate and positive action of the clamping jaw upon a steel plate upon which the clamp is positioned. l r l A still furtherobject of my invention is to provide an improved eccentric type cam operated steel plate lifting clamp which will provide an eccentric power gripping effect on the immediate as the description of the upwardly extending guide head 3 formed integrally with the bodyl. A split shacklelZ formed with an 'eye l3 in its outer end and with the oppositely extending eccentrics or cams l4 and IE on its lower end will be operatively supported over the guide head 3, upon the bearing pin I5" adapted to extend between the leg portions of the split shackle and through the elongated slot 4 in the guide head 3. The cam connecting links I6 will be connected between the which inturn will pull the plate clamping jaw 9 'outer ends of the bearing pin l5 and the outer end of the pivoted plate clamping jaw 9, whereby a rocking movement of the shackle I2 in either direction will cause the cam I 4 or I5 to rock along the bearing'surfaces H with a consequent immediate pull. on the cam connecting links 16,

into engagement with a plate in the clamp. A lifting cable with hook l1, will be connected to a suitable hoist (not shown), the said hook being adapted to hook into the eye I3 in the split shackle I2.

From the foregoing description, it will be apparent that in actual use, a workman will place a clamp on the opposite ends of a large steel plate, and as soon as the hoistbegins to exert a pull on the lifting cable and on the shackle, the eccentric or camming actionof the rockable cam shackle will cause the immediate action or gripping of the pivoted plate clamping jaws upon the steel plate, and the clamps will remain on the plate as long as there is any lift on the split shackle with its oppositely extending cams.

It will be apparent that many minor changes in detail of construction may be resorted to without departure from the spirit of the invention.

Having thus described my invention what I claim as new and desire to secure by Letters Patent of the United States is:

1. An eccentric type steel plate lifting clamp formed with a plate receiving slot in one edge thereof, a fixed jaw and a pivoted jaw mounted in the opposite sides of said slot, a guide head formed integrally with the clamp body and formed with an elongated bearing slot in 'alinement with the slot in the edge of the clamp body, a shackle adjustably supported in the slot in said guide head formed with cam surfaces adapted to engage and rock on bearing surfaces on. the clamp body at the opposite sides of the guide head, and cam connecting links between said shackle and said pivoted jaw. i

2. An eccentric type steel plate lifting clamp formed with a plate receiving slot in one'edge thereof, a fixed' jaw and a pivoted jaw mounted in'the opposite sides of said slot, an adjustable shackle having cam surfaces mounted on the clamp body and having a rockingengagement therewith, and cam links connected between said shackle and pivoted jaw whereby movement of the shackle will cause the operation of the pivoted jaw to engage a steel plate when in the slot in the clamp body.

- supported in the bearing slot in the clamp body formed with cam surfaces and links connecting said pivoted jaw and shackle for causing the actuation of the pivoted jaw upon movement of v the shackle with respect to the clamp body.

, 4. A steel plate lifting clamp including a body having a fixed jaw and a pivoted jaw, spaced bearing surfaces formed on theclamp body, a shackle carried by the clamp body formed with cam surfaces adapted'to ride onthe said bearing surfaces, and links connecting said pivoted jaw and shackle for causing the pivoted jaw to function.

5. A steel plate lifting clampincluding a bodyhaving afixed jawand a pivoted jaw, spaced bearing surfaces formed on the clamp body, a

shackle slidably mounted. on the clamp body and formed with oppositely disposed cams for riding on the bearing surfaces, and links connecting-said pivoted jaw and shackle for causing the pivoted jaw to engage a steel plate when in position withinthe-clamp.

a JOSEPH C. RENFROEJ' 

